New climate model for the IPCC

The mean global temperature trend from 1850 to 2100 according to the new AWI climate model. Credit: Tido Semmler

Researchers from the Alfred Wegener Institute now, for the first time, feed the results from their global models directly into the Intergovernmental Panel on Climate Change database. The data is particularly interesting because the underlying model, developed at the AWI, depicts the sea ice and the oceans with far greater definition than conventional methods. The results are used by climate scientists and stakeholders around the globe to determine the effects of climate change on humans and the environment.

How much warmer will the Earth become in the coming decades as a result of climate change? How will this change our world? These are some of the most pressing questions of our time, and researchers around the globe are using climate models in an attempt to find the answers. But Earth's climate is extremely complex and modelling it using super computers is difficult. Every climate model has its strengths and weaknesses. In order to better estimate the future climate developments, the results of various climate models around the globe are compared, since comparisons make it clearer which climate trend is most likely and what degree of uncertainty the prognoses possess. A total of about 50 research institutions worldwide are taking part in this extensive international project, known as the Coupled Model Intercomparison Project (CMIP). It is extremely important because the results are fed into an international database and form the basis for the next IPPC (Intergovernmental Panel on Climate Change, IPCC) report, which will be published in 2021—the Sixth Assessment Report, AR6.

Only three institutions from Germany

Now, for the first time, The Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), with its own model, is part of this major international comparison project. Just a few days ago, the AWI researchers entered their first detailed climate model results into the international CMIP database. "It's very special belonging to one of the institutions that make a significant contribution to the data that the Assessment Report will be based on," comments meteorologist Dr. Tido Semmler, who coordinates the AWI's work for the international comparison project CMIP. "There are only three research institutions from Germany involved—the Max Planck Institute for Meteorology in Hamburg, the German Aerospace Center and us." In addition, the German Climate Computing Center (DKRZ) in Hamburg plays a key role, since it offers the three institutions computer time and storage space as well as support in performing the simulations and the provision of data.

There's a particular reason why the AWI has now become involved: the experts have employed a new and, to date, little-used method to model the climate—a so-called "unstructured grid", which in terms of climate research amounts to a mini revolution. Until now, almost all the research groups around the globe have worked with what are known as "structured grids". The principal behind these grids is simple: since modelling the global climate is far too complex, researchers divide the Earth and the atmosphere into grid boxes, cubes with edges that are usually 100 kilometres long. In these boxes, the biological, chemical and physical processes that affect the climate can be modelled using supercomputers. But the fact that a length of 100 kilometres is much too crude to take important processes directly into account—like the small eddies, only a few kilometres in size, in the Gulf Stream and other ocean currents that lead to increased heat and moisture exchange between the sea and the atmosphere. Many climate models are unable to accurately depict the course of the Gulf Stream, which originates in the Gulf of Mexico and travels northwards along the Florida coast before veering eastwards towards Europe. In a lot of models the current moves much too far to the north due the small eddies not being included.

An adjustable grid

Ideally we would have a more finely meshed global grid with squares covering no more than ten kilometres. But that would increase the number of individual calculations. Even for climate simulations spanning just a few years, a mainframe computer would need several weeks. But experts at the AWI have now developed an alternative "unstructured grid". This allows the individual grid elements to be scaled down—to roughly ten kilometres—for certain selected regions. While the climate for the entire globe can be modelled using a grid with normal-sized squares, the flexibly adjustable mesh makes it to a certain extent possible to zoom in on specific regions, such as the Gulf Stream. The unstructured grid has added an interesting new dimension to climate modelling, which is highly important for the CMIP process.

A unique direct comparison

"As a rule, in climate modelling we combine various different models that simulate different things—for instance, a model that describes the ocean in detail and a second model showing the processes in the atmosphere," explains Tido Semmler. " The ocean model FESOM, which we developed, uses an unstructured grid. For the atmosphere, on the other hand, we use a conventionally structured model developed at the Max Planck Institute for Meteorology." This makes comparisons in the context of the CMIP particularly interesting: the Max Planck Institute for Meteorology couples the atmospheric model with its ocean model, which is based on the traditional grid. But the colleagues at the AWI couple the atmospheric model with their own ocean model, which uses the unstructured grid. "We and the CMIP partners are keen to see the direct comparison of these results," says Tido Semmler.

Important data for climate impact research

The results from the circa 50 climate models, which the AWI and the other CMIP partners are currently feeding into the international database, will be used by numerous other researchers during the next two years. Above all by those experts who are investigating the impact of climate change on people and habitats on our planet. These research findings will, in turn, be the basis for the IPCC reports; the 6th Assessment Report and also the summary of the IPCC's report, the Synthesis Report, which will mainly include policy recommendations.

Sample modelling results (see graphic online): The mean global temperature trend from 1850 to 2100 according to the new AWI climate model.

The AWI climate model includes the main natural drivers of the Earth's temperature, such as solar radiation, natural greenhouse gas and aerosol concentrations as well as volcanic aerosols. The grey line represents the control run with natural drivers and greenhouse gas concentrations of 284 ppm CO2 for the year 1850. The black line shows the historical mean global temperature trend with increasing greenhouse gas concentrations from 1850 up to 400ppm CO2 today, which have led to a net global warming of circa 1 °C. The coloured lines show the possible future development of the mean global temperature depending on the emission scenario.

The fluctuations in the lines show the natural variations in the mean global temperature without greenhouse gas emissions. For the historical trend (black line) and the moderate scenarios (circa 4 °C warming with 871 ppm CO2 in 2100) for the future (yellow line), several simulations were carried out to estimate the degree of uncertainty for the results. The AWI models have fluctuation range of roughly half a degree Celsius.

For the low emission scenario (445 ppm CO2 in 2100), there will need to be concerted efforts to reduce greenhouse gas emissions in order to limit the rise in mean global temperature to within 2 °C; with the high emission scenario (1142 ppm CO2 in 2100) it's assumed that no measures are taken to reduce greenhouse gas emissions, so that according to the present model the mean global temperature will rise by circa 5 °C.

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User comments

I have already mentioned that the beginning of chemtrails around 1950 led to a number of significant meteorological manifestations. Such as the development of the first new cloud species since the founding of the Cloud Atlas, cirrus intortus. And the only December hurricane on record, Alice, in 1955. And the number of tornadoes per year ceasing being a nearly constant 180 and skyrocketing to eight or nine times that number now. The graph at the top of this article demonstrates another manifestation. The gray line, control run, is the global temperature if the amount of carbon dioxide was the same as in 1850. The black line is the actual temperature. They diverge significantly after 1950! The gray line is what conditions would be with 1850's carbon dioxide. But much more carbon dioxide had been added since then, yet the black line was very close to the gray line! So carbon dioxide didn't cause the warming after 1950. That was caused by chemtrails!

"by Alfred Wegener Institute." ----- "The principal behind these grids is simple: since modelling the global climate is far too complex, researchers divide the Earth and the atmosphere into grid boxes, cubes with edges that are usually 100 kilometres long."

'Peer reviewed'? 'Cubes' are three dimensional. One hundred kilometers high? Just nit-picking.

When it comes to melding/averaging computer model outputs - I have very serious doubts.

Nice progress in modeling, not so nice in climate. We had record cyclone Idai and hurricane Dorian killing thousands respectively 50+ and raising in just one year, extreme weather predicted by AGW.

'Peer reviewed'? 'Cubes' are three dimensional. One hundred kilometers high? Just nit-picking.

Yes, as the article painstakingly detail. all the climate scientists is involved. Dunno about the geometry, but that would work since they average the results.

When it comes to melding/averaging computer model outputs - I have very serious doubts

Your personal incredulity means nothing, and even if it did you would be alone against all the 1000's of experts on the area that not only has no doubt but know it works: see the article figure! And the rest of us that reads this also know it since we read the article, so why use that phony argument (i.e. your non-expert sense of not understanding what is done)?

Go ahead, take a closer look of that image at the top. It will make no difference to the ignorant, but do it anyway.To label it, a mere fabrication, would be an injustice. As it is so much more.That there, is an abomination to science, aspiring to be a masterpiece of deception. But, just like all of its prior, increasingly preposterous, manifestations, it too shall fail. For anything that thick with lies shall inevitably shed its flakes.

Now all @tehgeighalgore has is a conspiracy theory about fake images. When they're images that show various predictions, not just one.

There's no honesty in that post. It's just more philosophical navel-gazing, and there's the result of resorting to navel-gazing. When no one looks at the predictions, Bayesian statistics rate the prior probability as zero, introducing a divide-by-zero flaw that they never acknowledge.

It is just data gathering. Amazing what fear can do, just amazing.Don't like the data? Does pooping your pants and screaming incoherently help? OK, yes it does because it is hard to think and scream at the same time, like a really stupid person trying to walk and chew gum at the same time.

All our records show a sharp upwards spike in 1998 and then a plateau in temperatures, but their "historical" record shows the exact opposite: a deep dip down in temperatures around 1998 and then a continuous rise up.

The 1998 peak was used by climate alarmist in the early 2000's to support rapid and costly interventionist policies and massive wealth transfers to the emerging renewable energy industries, as well as new taxation schemes, that have mostly proven themselves effective at increasing the size of governments and the pockets of "green" industrialists without actually reducing CO2 output. Remember the hockey stick graph? Now it seems this has been erased from history along with the plateau in warming, and the new model now shows a different story.

Eikka has a point. The models failed to predict the last 20 years. NOAA even tried to make the "hiatus" disappear as an artifact. The chart seems to show the current global temperature at ~15°C. What does that make the Northern and Southern hemispheres? The data from the two hemispheres are "gathered" and averaged to derive the global value. They tell us the NH is warming faster. How much warmer than the SH?

A November 2017 joint study by scientists at the University of Fairbanks and Beijing University found that when missing data from the rapidly warming Arctic were interpolated and included in global temperature averages, the so-called hiatus disappeared entirely.

The AWI (Alfred Wegener Institute) climate model includes the main natural drivers of the Earth's temperature, such as solar radiation, natural greenhouse gas and aerosol concentrations as well as volcanic aerosols

I notice they don't include cosmic radiation (ie. from outside the solar system) in their model. Arguably, this is quite damning, considering that cosmic radiation has been suggested as the potential primary driver of climate change, because of its alleged effects on the formation of low clouds which are crucial for reflecting sunlight, and thus heat, back into space.

gas concentrations from 1850 up to 400ppm CO2 today, which have led to a net global warming of circa 1 °C

If you actually read what I said, you'd see that I neither said I accept or deny the cosmic ray theory, just like I've never said that I accept or deny the CO2 theory. So, again, calling me a "denier" is yet more smear tactics from yourself. It seems that you do this a lot in order to dismiss people who don't bend the knee to your pet theory. It's rather disingenuous to paint those who wish to remain objective as "deniers".

As for your article, I'll have to take it with a huge pinch of salt, because the article makes a bunch of unsubstantiated allegations, and unlike yourself, I don't just read a single news article and decide that a certain theory is "nutjob" and "bullshit" (to quote you), just because a couple of scientists made some allegations. Instead, I do what ANY objectively-minded individual would do, which is wait patiently for a rebuttal from the scientists who specialise in the cosmic ray theory.

By the way, that article is from November 11, 2013. So that's 6 years out of date with the current research into Cosmic Ray theory.

The article I linked to you recently about Cosmic Ray theory - https://arxiv.org...0165.pdf - Is from June 29, 2019. So much more up to date. Yes, it's not peer-reviewed yet (afaik), but again, it's just a matter of having some time/patience and waiting for further research into the topic. Patience is a virtue.

As of yet, you have presented no meaningful rebuttal of the Cosmic Ray theory, despite your declaration of the theory as "nutjob" and "bullshit". You're literally choosing a 2013 news article over a 2019 scientific article. So I must ask: How deep does your bias go?

Uh, no it wasn't. It was a rebuttal presented in a news article, without evidence to back it up, six years ago. There has since been further research into the Cosmic Ray theory; the arXiv paper is one such example of that - And unlike the news article, it actually presents evidence that runs contrary to the claims made in said news article. So you could say that the six year old rebuttal has itself been rebutted. As I said, just be patient and wait for more research and rebuttals. Don't take a side. Be objective about it.

https://skepticalscience.com/print.php?r=277 - So cosmic rays are going *up* which Svensmark and you claim makes more clouds, which should cool things off by reflecting more, but instead the temperature is going *up* too

Firstly, that article is from 2013 (with data sets ranging between 2003 to 2013), so again, six years out of date with current research & evidence into Cosmic Ray theory. The arXiv paper arguably rebuts it.

Secondly, the claim "if the solar magnetic field were to increase, fewer GCRs would reach Earth, seeding fewer low-level clouds".. is ONLY true IF the magnitude of cosmic radiation remains constant. If cosmic rays increase (eg. due to a supernova or other cosmic event), an increased solar magnetic field can be counteracted.

Thirdly, the claim "the cosmic ray flux, although still behaving similarly to the temperature, in fact lags it and cannot be the cause of its rise" is rubbish, because there's NOTHING to say that a lagged effect can be causal.

Mr. Schneib? Accepting your very alarmed concern and dismissal or disagreement with evidence, What is your solution for the small rise in global temperature that was caused by a 45% increase in CO2 after several hundred years? What should the global community do about this CO2? Try to be specific about the amounts and the time it will take.

The article cites - https://skeptical...php?r=26 - But if you actually look at the graph (one side which I flipped to better demonstrate my point) - https://imgur.com/a/lhJrSLL - You can see that cosmic rays were higher (~4), they dipped down (~3.8-3.9), and went back up again (~4.1). You can also see that temperature change was level, it increased, then levelled off again, occurring all in the same time periods as each other. It's only correlation, and correlation doesn't equal causation, but this seems to counter the claim made by skepticalscience of no link at all.

My conjecture? I take no stance for or against. I merely mention alternative theories to show that there are more out there than just the monolithic CO2 theory.

Afaik, the Cosmic Ray theory doesn't involve just two variables (cosmic rays & global temperatures), but also third and fourth: Solar output & solar magnetic field strength. So really, you can have cosmic rays up, global warming down, just as you can have cosmic rays up, global warming up - it depends on the other factors too (and any other factors I'm unaware of wrt the cosmic ray theory).

Again, your use of the word "bullshit" is unjustified and uncalled for. Look at me - I don't go around calling CO2 theory "bullshit" and "nutjob". I remain as objective about it as I do cosmic ray theory. That seems intolerable to you.

The claim isn't made by SkepticalScience. I've already linked data from a paper in a peer reviewed scientific journal of record to support it. Maybe you forgot

You linked to an old/dated skepticalscience page, a more recent forbes article (which itself linked to a old/dated skepticalscience page), and a six year old/dated "news" article from scientificamerican.

Nothing you've linked to has refuted Cosmic Ray theory. I've even pointed out some issues with the articles too, questioning their conclusions about the data, such as the rubbish claim that lagged effects can never happen in nature. Is this the best you've got?

Fuck you in the heart, jack. Die screaming in agony. Preferably by drowning in the sewage the coastal sewage rope gangs are gonna string you up by your heels over while the tide comes in

That is very uncivilised rhetoric, and also rather unhinged of you. Please attempt to control your emotions & be objective about the science.

Fuck you in the heart, jack. Die screaming in agony. Preferably by drowning in the sewage the coastal sewage rope gangs are gonna string you up by your heels over while the tide comes in

This, ladies and gentleman, is the face of CO2 theory alarmism, if you attempt to remain objective & merely mention alternative theories. I smh at the abusive language & utter lack of civility on display.

Mr. Gutter-mouth Schneib. You have been politely asked to tell us what we should all do to lower the heat. It is not a political question, it is an engineering problem. Your further avoidance, coupled with personal attacks speaks volumes. Please try to be specific. Your alarm about the heat (0.83°C) is clear.

Da Schneib 18 hours agoHere's some quotes, and some further links:A November 2017 joint study by scientists at the University of Fairbanks and Beijing University found that when missing data from the rapidly warming Arctic were interpolated and included in global temperature averages, the so-called hiatus disappeared entirely.

Interpolation is an estimation of a value within two known values in a sequence of values. Polynomial interpolation is a method of estimating values between known data points.

In other words, the missing data points were "estimated" - not "measured". Reminds me of when the US Army was running telegraph lines to their various posts and forts in the US south-west. The telegraphist was expected to check the thermometer at midday. It had to be installed well away from any building. On some of the warmer days - "It's to damn hot to go out there, it feels like 116°." And that was the figure reported to HQ.

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